1. Field of the Invention
This invention relates to an apparatus and method for catheterization of the tissues and fluid spaces, including blood vessels, of the human body. The invention also relates to the method by which diagnostic and therapeutic agents and/or procedures may be delivered to any of those body parts or regions. In particular, the present invention relates to the design and use of a multi-lumen catheter for providing multiple, and not necessarily complimentery functions, such as sampling of the fluids within the extracellular and interstitial spaces of the brain, spinal cord, or other body tissues, concurrently with drug delivery, electrical recording/stimulating, or the delivery of any other type of therapy into the same tissues in accordance with the need for such therapies.
2. Background of the Art
Surgical procedures, especially neurosurgical procedures that involve open craniotomy, carry an intrinsically high level of risk of infection and hemorrhage. A variety of new techniques aimed at minimizing the invasiveness of interventional procedures have been introduced in the hope of reducing the surgical risk and shorten a patient""s hospital stay and overall rehabilitation. Placement of probes and catheters into the brain using stereotactic and image-guided procedures provides one means of minimizing these risks. However, many types of interventional procedures, including those that require drug delivery into the brain, sometimes require either catheterization at multiple target points, or subsequent re-implantation of the catheter to optimize the therapy being delivered to the brain.
Current methods of catheterization of the parenchymal tissues of the brain make it possible to measure intracranial pressure (U.S. Pat. No. 5,107,847), deliver drugs in a rate-controlled manner (U.S. Pat. No. 5,836,935), infuse various substances into the brain (U.S. Pat. No. 5,720,720), and convey fluids out of the brain (U.S. Pat. No. 5,772,625). Very recent technological developments are now leading to intraparenchymal catheterization systems that can be positioned within the brain by magnetic stereotaxis (U.S. Pat. Nos. 5,125,888; 5,707,335; 5,779,694), that are visible under magnetic resonance (MR) imaging (U.S. patent application Ser. No. 09/131,031 and U.S. Pat. No. 6,026,316), and that contain multi-purpose electrodes (U.S. Pat. No. 5,843,093). In addition, there are several types of implantable neurostimultor devices that have been disclosed. These include those described by Otten (U.S. Pat. No. 5,344,439), Hess et al. (U.S. Pat. No., 4,800,898), and Tarjan et al. (U.S. Pat. No. 4,549,556) as three examples thereof. However, none of the available methods of intraparenchymal catheterization can carry out multiple input-output functions at the same time with the same implanted device. With the exception of the method taught by Otten (U.S. Pat. No. 5,344,439), an already implanted device or part of an implanted device must be withdrawn before another probe is subsequently inserted into the tissue to perform additional functions. U.S. Pat. No. 5,788,713 describes the availability of both a delivery lumen and sampling lumen on a single catheter system.
One of the significant problems with delivering drugs directly into living tissue is assuring that the drug is accurately distributed to target receptor locations. The efficacious delivery of therapeutic agents for the treatment of brain tumors or neurodegenerative diseases, as two examples, requires that the agents be delivered as close to their receptors in the brain as possible, while minimizing increases in intracranial pressure during and after drug delivery. Liquid drug agents delivered into the brain through implanted catheters will disperse from the site of injection at variable rates depending on a number of factors, including the physicochemical characteristics of the drug, capillary uptake, metabolic degradation and excretion of the drug, size of the extracellular space, geometry of the brain cell microenvironment and input flow-rate and line pressure of the infusion system or other device that is pumping the drug into the brain. The degree to which each of these factors influences the distribution of a particular drug agent may be an important determinant of the effectiveness of drug treatment of diseases of the central nervous system. Additionally, the inventors have determined that it is increasingly important to determine other local characteristics of the region where active materials are delivered that can effect the efficacy or optimization of the treatment, such as pH, osmololity, viscosity, electrolyte content, temperature, fluid flow rates, and concentrations of specific ingredients. No present systems enable both the delivery of therapeutic materials and the measurement of significant local properties (except for the single noted instance of delivery and physical sampling).
Ideally, the injected, infused, or retroprofused material (e.g., a material that is xe2x80x9cbiologically active,xe2x80x9d that is a material which influences, increases, decreases or supplements biological activities on the cellular or macro-organ level, such activities, for example, including any chemical production, cell reproduction, hormone production, enzyme production, responsive activity, and the like) infiltrates the extracellular space, and the subsequent distribution of the drug within the tissues is governed mainly by its molecular weight, molecular radius, the structure and hydraulic conductivity of the tissue matrix into which the material has been injected, and the hydrodynamics of the infusion process. However, various flow scenarios may lead to tissue swelling, an increase in ICP (intracranial pressure) and, secondarily, altered interstitial transport of the drug solute.
Invasive ICP devices have generally evolved in two basic directions. The first is based on implanting a sensor within the cranium. The second is based on mounting the sensor externally and connecting the measurement site through a fluid-filled transmission line. The three main sites for ICP monitoring are the lateral ventricle, the extradural space, and the subdural or subarachmoid spaces.
U.S. Pat. No. 4,014,319 to Favre discloses an intracranial pressure transducer comprising a small sealed capsule positioned in a trephined hole in the patient""s skull, wherein a sensor diaphragm in contact with the dura mater is displaced by changes in intracranial pressure and produces an output signal proportional to the change in intracranial pressure. U.S. Pat. No. 4,026,276 to Chubbuck discloses a pressure monitoring apparatus implantable in the cranium, wherein the apparatus comprises a passive resonant circuit with inductance and capacitance capability for measuring intracranial pressure by comparison to a reference ambient pressure. U.S. Pat. No. 4,062,354 to Taylor, et al. discloses an intracranial pressure transducer system comprising a holding bracket containing sensor elements which is positioned against the dura of the brain, wherein the elements within the holding bracket transmit electromagnetic signals related to the intracranial pressure to a receiver outside the patient""s body. U.S. Pat. No. 4,080,653 to Barnes, et al. discloses a method and apparatus for recording intracranial pressure utilizing a transducer amplifier. U.S. Pat. No. 4,114,603 discloses an intracranial pressure monitoring device comprising a pressure-sensitive catheter insertable between the dura mater and arachnoid membrane.
U.S. Pat. No. 4,114,606 discloses a monitoring apparatus for intracranial pressure measurement, wherein electromagnetic radiation is imposed on a passive circuit implanted in the cranium, the frequency at which the radiation is absorbed reflecting intracranial pressure. U.S. Pat. No. 4,147,161 to Ikebe, et al. discloses a system for measuring or monitoring intracranial pressure which comprises a non-elastic detecting pouch inserted between the skull and the brain, wherein a pressure measuring device in the liquid in the pouch indirectly measures the intracranial pressure. U.S. Pat. No. 4,156,422 to Hildebrandt discloses an apparatus for treating hydrocephalus comprising a housing which contains subcutaneously implantable components for measuring and controlling fluid pressure, wherein a second housing outside the patient contains measuring and control components whereby an intracerebral space may be automatically drained in response to a predetermined adjustable ICP.
U.S. Pat. No. 4,210,029 to Porter discloses a differential sensor unit utilizing fiber optic light guides, wherein three light guides pass within a pneumatic line into one end of a rigid cylindrical envelope implanted in the skull. Detectors are arranged to actuate pressure display and pneumatic controls to adjust the internal pressure of the envelope to match the ICP and thereby measure the ICP. U.S. Pat. No. 4,265,252 to Chubbuck discloses an implantable transensor device containing a passive RF resonant circuit which is responsive to changes in ICP. U.S. Pat. No. 4,385,636 to Cosman discloses an implantable telemetric differential pressure sensing device comprising a planar closed conductive loop which moves with a flexible diaphragm, wherein the resonant frequency of the conductive loop is detected telemetrically to determine pressure in a body compartment.
U.S. Pat. No. 4,340,038 to McKean discloses a magnetic field generator and magnetic pick-up coil contained in an implanted ICP monitoring device. U.S. Pat. No. 4,354,506 to Sakaguchi, et al. discloses an intracranial pressure gauge which comprises a powerless resonance circuit composed of a coil and a condenser, a sensor equipped with an implantable pressure-sensitive section capable of changing the inductance or the capacitance of the condenser in response to a change in ICP. U.S. Pat. No. 4,438,773 to Letterio discloses an implantable subarachnoid bolt for use in measuring ICP.
U.S. Pat. No. 4,465,075 to Swartz discloses an integrated circuit including a pressure transducer and temperature compensation circuit. U.S. Pat. No. 4,471,786 to Inagaki discloses a telemetering intracranial pressure transducer for detecting ICP, wherein a pressure-receiving layer disposed in contact with the dura mater transmits an output signal to a telemetering transmission circuit housed entirely beneath the patient""s scalp. U.S. Pat. No. 4,600,013 to Landy, et al. discloses a probe for ICP measurements in the subarachnoid space, said probe comprising a threaded shaft having a lumen in contact with a pressure transducer. U.S. Pat. No. 4,621,647 to Loveland discloses an apparatus for monitoring and regulating ICP, wherein a manometer, transducer and regulator are interconnected by tubing and stopcocks.
U.S. Pat. No. 4,627,443 to Chubbuck, et al. discloses an X-ray readable implantable pressure sensor, wherein shifting of a radiopaque means is observed to indicate the change in pressure of a body cavity. U.S. Pat. No. 4,677,985 to Bro, et al. discloses an intracranial probe to monitor both ICP and blood flow by thermal diffusion and hydrogen clearance techniques. U.S. Pat. No. 4,703,757 to Cohen discloses an optical fiber pressure transducer, wherein variations in transversely applied pressure to an elongated flexible fiber results in proportional light refraction and corresponding output signal.
U.S. Pat. No. 4,711,246 to Alderson discloses a miniaturized pressure transducer, wherein light transmitted through a single optical fiber is reflected by a diaphragm in accordance with the pressure being measured. U.S. Pat. No. 4,723,556 to Sussman discloses an intracranial ventricular catheter assembly, wherein a pressure sensing device is connected to the proximal catheter. U.S. Pat. No. 4,738,267 to Lazorthes, et al. discloses an implantable intracranial pressure sensor, wherein a pressure-sensitive diaphragm placed directly on the dura mater transmits the intracranial pressure through a resistive type transducer.
U.S. Pat. No. 4,772,257 to Hakim, et al. discloses an external programmer for magnetically-adjustable cerebrospinal fluid shunt valve. U.S. Pat. No. 4,858,619 to Toth discloses an intracranial pressure monitoring system, wherein relief valves are combined with a pressure sensor for automatic venting of cerebrospinal fluid during elevated ICP. U.S. Pat. No. 4,805,634 to Ullrich, et al. discloses an adapter assembly for accurately positioning a removeable biosensor implanted in the cranium. U.S. Pat. No. 4,841,986 to Marchbanks discloses a method and apparatus for measuring ICP, wherein a pressure sensor placed against the eardrum indirectly detects ICP changes based on displacement of the eardrum.
U.S. Pat. No. 4,903,707 to Knute, et al. discloses a ventricular catheter assembly comprising a catheter and a bolt, wherein the catheter can be inserted to a predetermined depth into the cranium. U.S. Pat. No. 4,995,401 to Bunegin, et al. discloses a device for measuring anterior fontanelle pressure, wherein ICP changes can be detected noninvasively. U.S. Pat. No. 5,000,049 to Cooper, et al. discloses an apparatus for measuring fluid pressures using a catheter device. U.S. Pat. No. 5,005,584 to Little discloses a fiber optic transducer utilizing a flexible membrane to transduce pressure by interrupting light transmission between fiber optic paths in a catheter or guide wire carrier.
U.S. Pat. Nos. 5,074,310 and 5,117,835 to Mick disclose a method and apparatus for non-invasively measuring changes in ICP, wherein a predetermined vibration signal is applied to one location in the skull and an output vibration signal is detected from another location in the skull, reflecting ICP changes over time. U.S. Pat. No. 5,108,364 to Takezawa, et al. discloses a monitoring catheter for medical use comprised of multiple tubes equipped for fluid delivery and removal, pressure measurement, and temperature measurement. U.S. Pat. No. 5,113,868 to Wise at al discloses a pressure sensing catheter system comprising a catheter, a pressure sensor, and a signal conduit means within the catheter for signals between an external monitor and the pressure sensor, the signal conduit including two electrical conductors which are connectable to the external monitor. U.S. Pat. No. 5,191,898 to Millar discloses a cerebroventricular catheter means of measuring ICP and injecting or withdrawing cerebrospinal fluid, wherein a transducer positioned at the end of the cerebroventricular catheter and electrically coupled to a monitor allows for ICP monitoring.
Guidewires for the catheter or drug delivery system are usually made of radiopaque material so that their precise location can be identified during a surgical procedure through fluoroscopic viewing. Exemplary of guidewires used under X-ray viewing is the guidewire disclosed by LeVeen, U.S. Pat. No. 4,448,195, in which a radiopaque wire can be identified on fluoroscopic images by metered bands placed at predetermined locations. The U.S. Pat. No. 4,922,924, awarded to Gambale et al. discloses a bifilar arrangement whereby radiopaque and radiotransparent filaments are wrapped on a mandril to form a bifilar coil which provides radiopaque and radiotransparent areas on the guide wire. U.S. Pat. No. 5,375,596 to Twiss et al. discloses a method for locating catheters and other tubular medical devices implanted in the human body using an integrated system of wire transmitters and receivers. U.S. Pat. No. 4,572,198 to Codrington also provides for conductive elements, such as electrode wires, for systematically disturbing the magnetic field in a defined portion of a catheter to yield increased MR visibility of that region of the catheter. However, the presence of conductive elements in the catheter also introduces increased electronic noise and the possibility of Ohmic heating, and these factors have the overall effect of degrading the quality of the MR image and raising concerns about patient safety. Thus, in all of these examples of implantable medical probes, the presence of MR-incompatible wire materials causes large imaging artifacts. The lack of clinically adequate MR visibility and/or imaging artifact contamination caused by the device is also a problem for most commercially available catheters, microcatheters and shunts. MRI enables image-guided placement of a catheter or other drug delivery device at targeted intracranial loci. High-resolution visual images denoting the actual position of the drug delivery device within the brain would be extremely useful to the clinician in maximizing the safety and efficacy of the procedure. Drug delivery devices, such as catheters, that are both MR-visible and radio-opaque could be monitored by both X-ray fluoroscopy and MR imaging, thus making intra-operative verification of catheter location possible.
U.S. Pat. No. 5,291,899 to Watanabe, et al. discloses a method for measuring ICP by using a device comprising a reservoir implantable under the skin of a patient and into which cerebrospinal fluid can be introduced from the ventricle of the patient, a flexible dome configured to be upwardly projected from said reservoir by the pressure of the cerebrospinal fluid and flexibly deformable according to an external force, a pressing part for pressing against said dome through the skin, a pressing-part-driving means for driving said pressing part pressing the dome and a flexible membrane provided at the tip of the pressing part and having an interior filled with a fluid, the method comprising: pressing the flexible membrane of the pressing part against the dome of the reservoir through the skin by means of the pressing-part-driving means after a zero point correction of the pressure transducer is performed by communicating the interior of the flexible membrane with the atmosphere.
U.S. Pat. No. 5,325,865 to Beckman, et al. discloses a catheter assembly for measuring fluid pressure in a body cavity, comprising an optical converter responsive to an electrical power source for energizing a light-emitting diode which has drift characteristics which vary in response to temperature, and a detection circuit.
U.S. Pat. No. 5,230,338 to Allen, et al. discloses an interactive image-guided system for displaying images corresponding to the placement of a surgical probe in the body. U.S. Pat. No. 4,173,228 to Van Steenwyk, et al, and U.S. Pat. No. 5,042,486 to Pfeiler, et al. disclose medical probes wherein electromagnetic signals are propagated between one antenna on the tip of the probe inserted into a body region and several antennae outside the body. The position and orientation of the probe tip are determined from the signals transmitted between said antennae. U.S. Pat. Nos. 5,211,165 to Dumoulin, et al, U.S. Pat. No. 5,255,680 to Darrow and Dumoulin, U.S. Pat. No. 5,307,808 to Dumoulin, et al., and U.S. Pat. No. 5,318,025 to Dumoulin, et al. additionally disclose a tracking system in which radiofrequency signals emitted by an invasive device, such as a catheter, are detected and used to measure the device""s position and orientation in a patient. Localization of a device in situ is achieved by transmit radiofrequency coils positioned at its distal end, which are detected by receive radiofrequency coils positioned around the imaging volume of interest. The position of the device, as determined by the tracking system, is superimposed upon independently acquired diagnostic images. U.S. Pat. No. 5,383,454 to Bucholz discloses a system for indicating a position of a tip of a probe which is positioned within an object on images of the object, wherein a computer employing translational software translates the position of the tip of said probe into a coordinate system corresponding to the coordinate system of the cross-sectional images.
Each of the above-cited patents provide advantages and disadvantages for monitoring of ICP and other tissue parameters related to intracranial drug delivery. For instance, intraventricular catheters are accurate but may be difficult to position in the presence of brain swelling and shift. Subarachnoid devices are easily placed but may underestimate higher ICP pressures, particularly if they are not coplanar to the brain surface. Epidural devices require placement through a burr hole and can be hampered by recording artifacts, damping, and problems with calibration. (We note that Raabe and colleagues have published an article in Neurosurgery, Vol. 42, No. 1, pps. 74-80, 1998, that discusses techniques that attempt to avoid certain methodological errors that arise in the use of some ICP measurement devices.) Moreover, none of the above cited patents disclose a method and means for evaluating changes in ICP resulting from the direct injection or infusion of drug agents into brain tissues as does the present invention.
U.S. Pat. No. 5,843,093 to Howard discloses a dual purpose neuron-monitoring electrode assembly particularly suited for performing magnetic pallidotomy for the treatment of Parkinson""s disease. However, unlike the present invention, the patent to Howard does not provide for an MR-compatible, multi-lumen probe which is capable of containing several different internal devices that can sample the extracellular environment and react to it.
U.S. Pat. No. 5,843,150 to Dreessen, et al. discloses a system and method for providing electrical and/or fluid treatment within a patient""s brain, wherein the device is an implantable device comprising a lumen, a catheter, an electrode, and a pump. However, unlike the present invention, the patent to Dreessen, et al. does not provide for an MR-compatible, multi-lumen probe which is capable of containing several different internal devices that can sample the extracellular environment and react to it.
U.S. Pat. No. 5,861,019 to Sun, et al. discloses a telemetry system for communications between an external programmer and an implantable medical device. However, unlike the present invention, the patent to Sun, et al. does not provide for an MR-compatible, multi-lumen probe which is capable of containing several different internal devices that can sample the extracellular environment and react to it.
U.S. Pat. No. 5,843,148 to Gijsbers, et al. discloses a brain stimulation lead and multiple electrodes for precise delivery of electrical stimuli to a patient""s brain. However, unlike the present invention, the patent to Gijsbers, et al. does not provide for an MR-compatible, multi-lumen probe which is capable of containing several different internal devices that can sample the extracellular environment and react to it.
U.S. Pat. No. 5,820,589 to Torgerson, et al. discloses an implantable medical pump comprising a fluid reservoir, a passive regulator assembly, an electromechanical controls means, and a means for receiving radio frequency signals to operate the electromechanical control means. However, unlike the present invention, the patent to Torgerson, et al. does not provide for an MR-compatible, multi-lumen probe which is capable of containing several different internal devices that can sample the extracellular environment and react to it.
U.S. Pat. No. 5,821,011 to Taylor, et al. discloses a device for implantation in a human body in contact with body fluids, which includes an electrical terminal, a glass insulator, and a sleeve positioned between the glass insulator and a container. However, unlike the present invention, the patent to Taylor, et al. does not provide for an MR-compatible, multi-lumen probe which is capable of containing several different internal devices that can sample the extracellular environment and react to it.
U.S. Pat. No. 5,826,576 to West discloses an electrophysiology catheter which includes a handle, a catheter shaft with a flexible tip portion with one or more electrodes, a multifunction wire extending along the catheter shaft, and one or more micromanipulators. However, unlike the present invention, the patent to West does not provide for an MR-compatible, multi-lumen probe which is capable of containing several different internal devices that can sample the extracellular environment and react to it.
U.S. Pat. No. 5,858,009 to Jonkman discloses a multi-lumen cannula for conducting fluid to and from a body region, especially in left-heart and right-heart assist cardiac surgical procedures, wherein the septum separating the first and second catheter lumens is wire-reinforced to resist deflection of the septum.
PCT application WO9807367A1 to Jolecz, et al. discloses image-guided means and apparatus for ultrasound delivery of compounds through the blood-brain barrier to selected locations in the brain.
A multi-lumen catheter system with novel forms and functions is disclosed. A desirable design feature for practice of this invention comprises an elongate element, such as a central barrel of a catheter which is surrounded by (or including within a major lumen) additional lumens which perform or transport various functions. In one embodiment that is particularly useful for therapy of the parenchymal tissues of the brain, one or more of the plurality of lumens around the central barrel are configured for sampling of fluids within the interstitial space (e.g., semiconductor based, microdialysis-based, electronically based, electrically based, interactance and transmittal, etc. sampling). Other lumens of the multi-lumen probe can be used for the delivery of drugs, therapeutic agents, diagnostic agents or view-enhancing agents into the parenchymal tissues, either via efflux from a single drug delivery lumen or via a multi-port configuration to facilitate broad spatial distribution of the drug within the tissue. In this embodiment, the central lumen can be used for any treatment or function, but especially either microdialysis or drug delivery, or it can be configured to accommodate a recording or stimulating electrode, such as a multi-purpose stereotactically placed electrode (e.g., U.S. Pat. No. 5,843,093). In a method of the invention, additional probes or devices that might be passed through either the central barrel of the catheter or through one of the surrounding ports include intracranial pressure probes, optical fibers and/or optical fiber bundles configured for conveying illumination and/or optical signals to and from the target tissues, iontophoresis probes, thermometry probes, blood-flow-sensing probes, chemical probes, sensing devices (even audio sensing devices, pressure-sensing devices, pH sensing devices, viscosity or osmololity sensing devices, radiation-sensing device, light-sensing device, etc.), vacuum lines, fluid delivery tubes and conduits, guidewires, fixed and adjustable-tipped steering probes and wires, electric field and magnetic field-sensing probes, electrodes and applicators, gene analysis chips and xe2x80x9clab-on-a-chipxe2x80x9d structures, biopsy devices, tissue and cell implantation devices, cryogenic probes, thermal probes, ablation probes, cauterizing probes and tips, stents, coils, angioplasty balloons and devices, radioactive sources, magnetic and electric field sources, integrated circuits and electronic devices.
The unique compound nature of the catheter which is the subject of the present invention makes it possible to carry out several diagnostic and therapeutic tasks concurrently, with or without additional functional coupling between the processes. An important attribute of the medical device disclosed by this invention is to optimize the therapeutic response to the patient""s clinical condition by using the sampling capabilities of the microdialysis or other diagnostic components of the catheter to provide information on the metabolic state of the target tissue (especially the brain) via analysis of the fluids within the extra-cellular matrix. Drug delivery into the parenchymal tissues can then be carried out via positive pressure infusion, or by diffusion-based delivery of pharmacological agents via the microdialysis process, using available lumens within the catheter to carry out either form of treatment. In parallel with drug delivery, electrostimulation of the same or nearby target tissues/neurons can be carried out via a recording/stimulating electrode passed down a central or radially disposed barrel of the device.
In a method of the invention, a feedback mechanism may be used to automate and optimize the entire process, wherein a number of physiological variables can be taken into account by an algorithm that governs the therapeutic response of the catheter system. In another embodiment, physiological and metabolic data on the status of the patient (derived form other sensors on/in the body, such as, for example, probes which monitor tissue oxygen levels, blood pH, concentration of materials in the blood, blood flow, and other physiologic parameters) can be incorporated into the algorithm""s treatment optimization process. Thus, for example, if a stroke or brain-injury patient were in an intensive care unit or other hospital bed setting, the vital-signs data from patient monitoring systems (including, in particular, intracranial pressure measurements) could be monitored by the system""s signal processor, wherein the resulting information provided feedback control of the rates of drug flow into the brain. In another embodiment of the method of the invention, the microdialysis systems of the catheter device are used to sample endorphin levels, wherein the catheter""s signal processor could then provide feedback control of the electrostimulation process so as to attenuate the effects of chronic pain.
In another embodiment of the method of the invention, the algorithm governing the patient""s therapy preferably utilizes proportional-integral-derivative (PID) control functions, adaptive control functions, nonlinear control functions, multi-variable/state-space control functions, stochastic control functions and/or any other functional approach deemed appropriate for the implementation of the therapy. In all such cases, the controller could be designed to respond to changes in the patient""s condition using artificial intelligence techniques that would let the feedback mechanism xe2x80x9clearnxe2x80x9d the best way to respond to changes in the patient""s physiological or anatomical status. Such techniques might employ, among other things, xe2x80x9cfuzzy logicxe2x80x9d algorithms that can function in the presence of incomplete or indeterminate data.
A summary of the present invention includes at least a multi-lumen, multi-functional catheter system comprising a plurality of axial lumens, at least one lumen supporting a functionality other than material delivery and material removal. At least two individual lumens may be parallel to a central barrel of the catheter, and at least one of the at least two lumens may be used for sampling fluids in a body part into which the catheter is inserted. At least one of the axial lumens may be used for infusion, injection or other mechanism of delivery of diagnostic and/or therapeutic agents into a body part in which the catheter is inserted. The central lumen of the catheter may contain an electrode, such as a neurostimulator or radiofrequency-ablation lead. An outer surface of the catheter may comprise a continuous sheath inside of which are located individual lumens, a central barrel and other functional components of the catheter system. At least some of said other function components may comprise electrical leads. There does not have to be an envelope around the catheter system, so there need not be any exterior covering element over the at least two lumens, a central barrel and other functional components of the catheter system. It is expected that at least one biological or physiological measuring device is present within at least one lumen. Such a biological or physiological measuring device would be expected to be connected to a signal receiving device by an electrical lead associated with the catheter system. The at least one biological or physiological measuring device may connected to a signal receiving device by an electrical lead permanently attached to the catheter system. The at least one diagnostic component may provide any useful information, such as information about metabolic, physiologic and/or anatomic status of a patient. The information from said at least one biological or physiological measuring device would ordinarily be received by a host computer connected to said device. More than one component or sensing element or measuring device would be among components that provides information other than information from said at least one biological or physiological measuring device. All or most of that information should be received by a host computer to evaluate a treatment procedure or patient conditions around the locality of treatment. The additional components may measure, for example, vital signs of a patient. Information from more than one information source may received by the host computer and a treatment planning and control algorithm could be present in said host computer to process that information from more than one source.
A method according to the invention for treating a patient according to a treatment plan could comprise inserting the catheter system the invention into a patient, delivering therapy to the patient through at least one lumen of said catheter system, taking biological or physiological measurements of tissue or fluids within the patient, reporting said information to a computer, and evaluating performance of the treatment plan with the computer based upon comparing said information to expected biological or physiological information. The method could include information relating to at least two different biological or physiological measurements being electrically transmitted to the computer for evaluating performance of the treatment plan. Upon evaluation of the performance of the treatment plan, the computer could indicate a) a deviation for a range of acceptable levels of performance of the treatment plan, and b) an alteration of an existing treatment plan is identified. The method could have the computer signal the catheter system to actively modify the existing treatment plan. The method could also include having the computer signal an operator to actively modify the existing treatment plan.